Besides being a DotNet developer I've spent some part of my life (3 odd months) in the past, being a Linux Administrator. Every guy in the Linux world loves the bash Auto-complete feature. The part where you type the partial name of file or directory and hit the tab button and the console completes the typing of the entire file / directory name for you.
I just think it's Natural (and super cool) for an OS to be able to reduce the number of clicks (or keystrokes, for that matter) and help you get to where you want to get faster.
The Windows CMD.EXE had started supporting this feature; since, I don't when. I don't recall when I hit the tab key while I was working in the Dos Console. The Auto complete worked (just like Linux bash). In fact it worked so smoothly that I didn't even realize or think about the fact that it wasn't supposed to work! I was in DOS (CMD.EXE of windows 2003 server edition), not Linux!
Anyway, so basically, what I am trying to say is that I've been using the Auto Complete on tab feature of MS-DOS without even knowing / realizing / remembering since how long I've been using it. Recently I showed this to another Linux IT guy who was working in MS-DOS and his reaction was - "Wow! I didn't know Dos Supports This!"
So, basically looks like this feature has been a part of MS-DOS for a VERY long time and most IT guys I've worked with or talked to don't even know / remember when this feature became a part of MS-DOS.
Recently I reinstalled Windows 2003 Server on my laptop (I was having problems with a direct install coz my Dell 700m would just hang - so I had to install windows 2000 and then upgrade to 2003) after a format and a "fresh start" and discovered that the Auto Complete on Tab feature wouldn't work any more!
As it turns out, this is a feature that may / may not be enabled on your machine by default. If you've upgraded from Windows 2000 or a previous OS to Windows 2003 Server this feature may be disabled by default. Enabling it is simple though.
Use the registry editor and change the value of HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Command Processor\CompletionChar from 0x40 to 0x9
I had a difficult time Goggling an answer for this problem so I thought I'd post it here. Here's the URL where this Information originally comes from. (Just so that I give Due credit to the guy for posting the solution :) )